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2rangers
09-08-2005, 16:05
Gundoc-
You are a well trusted member of this BBS, and as I said before, your reputation precedes you. That's why I have no reservations about asking you a gunsmith-related question. So here goes:

Not long ago, I was given a Santa fe jungle carbine. It's basically a stand. no.4, that has been modified(not really bubba-fied) to resemble a No.5 jungle carbine.
Golden state arms did the conversion, but I'm not exactly sure when. Everything seems to be in decent shape, w/ the exception of the chamber. The bore had some minor surface rust, but after a thorough cleaning, the pitting is minimal.

The best part is that this rifle was FTR'd at some point around the late '40's-early '50's, and not shot too much since that.(the rifling is pretty crisp). The barrel, although def. a brit. issue barrel w/ left hand twist and proof marks, is MUCH thicker in dia. than a standard No.5 barrel, even thicker than my other No.4's. I hope this will translate to even better accuracy, and less heat-induced poi shift. The entire rifle was then parked pretty well, and has no traces of the factory baked enamel, wich is another plus in my book. BTW- I posted a pic in the gallery. I'd give you a link, but I don't know how.

There's the pre-text, so now for the question.
As I said, there seems to be a problem w/ the chamber. The fired brass has a peculiar bulge in the shoulder area. This is w/ both fact. ammo, and reduced load handloads. I scoped the chamber, and sure enough, there is a corresponding bulge in the shoulder area of the chamber, from the 7 o'clock to 9 o'clock positions. Not rough, but like it was eroded gently, as if by corrosion, but smooth in nature. As smooth as the rest of the chamber. The remainder of the chamber is actually at minimums, and the fired brass is expanded only minimally. Much less than any of my wartime-made enfields, w/ "generous", function-with-mud-dirt-etc.-chambers.

I am thinking of re-chambering the barrel, and going w/ an improved case design-.303 Epps. Sort of like a P.O. Ackley improvement, but not as severe. The cartridge will continue to headspace on the rim, ala traditional .303 brit. I plan on fire-forming my cases w/ light loads, and neck-sizing thereafter. I am also thinking of getting the throat re-cut at the same time, as there is slight throat erosion. Headspace shouldn't change too much, and I can always correct it w/ a new bolt head, if necesaary. I have researched new loads for this cart., and pressure will still be below 45,000 cup, a safe max. ave. pressure for .303 brit/enfield actions.

I plan on having a local reputable smith do this, as, no offense intended, I like face-to-face business dealings; a firm handshake still holds worth to me. I just wanted to get your opinion, as you are a wealth of knowledge, and who knows, may have done a similar job in the past.

I thank you in advance for your reply,
Carlo :sniper:

gundoc
09-08-2005, 18:42
I appreciate the accolades and no offense taken to the other smith....we all gotta eat! If the chamber reamer is available it is a simple matter to do it and set the barrel back for cutting the throat and headspace. If the chamber reamer has to be made that can be expensive. As you want another smith to do it, I would ask him his opinion and whether or not he is comfortable doing it. With the research you have done for pressures and measurements, i would feel comfortable with this mod. Good luck and let me know how it turns out!

Doc

Tailgunner
09-09-2005, 03:49
Ummm, just 1 point. To insure proper headspacing with a rimless cartridge you should set the barrel back when going " Ackley improved" , however it's not necessory to do a setback when improving a rimmed or belted cartridge as the HS datum dosn't change.
The Epps chamber does require a setback of the barrel, and it is 1 thread length shorter than the 303Brit (Epps is a simple mod that allows the use of surplus rifles in areas that don't allow the civilian use of "military" cartridges")

gundoc
09-09-2005, 18:32
True, but if rechambering why not set back and recut to get past the throat erosion if that is a concern? I prefer not to set back a barrel unless I have to or am requested to. Some shooters like to shorten up the free bore on their rifles and I accomodate when I can.

Doc

2rangers
09-09-2005, 19:15
Gundoc, Tailgunner-
First of all, thanks for the quick reply, Gundoc. I was supposed to drop the rifle off today, but I had to work late, and didn't get there in time. Thankfully, when I called the smith, he was very understanding, and will let me bring it over on sat.

As far as setting the barrel back, yes, the reason I wanted to was to lessen the freebore some, and cut a new throat. It would be silly to go thru the effort of cutting a new chamber and not taking advantage of the reamer while it was "in there".

I am thinking that if I can get this rifle shooting pretty well- it should, as the barrel is thicker, and the rifling is still crisp, I will return my other No.5 to it's original, unadulterated state, as it's still in overall about NRA 80-85%. Decent looking, original enfields that haven't been hacked by "bubba" are getting harder to find.

I just really like this rifle for hunting on the stalk. It's short(20" barrel), fairly light, although it kicks pretty violently. And a 180 grain Sierra pro-hunter loaded for 2400 fps stops deer dead, providing I do my part. BTW- I've found that the 150 grn. hornady and sierra have produced thru-and thru's at 2700 fps.(Albeit they were smaller does.) The 180 grn, going a little slower, mushrooms really nice, and I've never had one exit. Never weighed the recovered bullet, but it was still together pretty much. I only wish Nosler made an accubond for this caliber, as I've been told their terminal performance is just about miraculous!.
:sniper:

2rangers
09-09-2005, 19:20
Originally posted by Tailgunner@Sep 9 2005, 01:49 AM

The Epps chamber does require a setback of the barrel, and it is 1 thread length shorter than the 303Brit (Epps is a simple mod that allows the use of surplus rifles in areas that don't allow the civilian use of "military" cartridges")
Tailgunner-
Is that why .303 Epps was created? I guess that's why Ruger made mini's in, I believe, either .222 rem. or .222 rem mag? :sniper: